distributed_physics_test/src/net/plugin.rs

use std::net::SocketAddr;

use bevy::prelude::*;
use uuid::Uuid;

use super::{
    io::{handle_network_input, handle_network_output, heartbeat, timeout},
    packet::{InboundPacket, OutboundPacket},
    peer::{PeerChangeEvent, PeerData, PeerMap, handle_new_peer, handle_peer_change},
    queues::{NetworkReceive, NetworkSend},
    socket::bind_socket,
    state::NetworkState,
};

pub struct NetIOPlugin {
    listen: u16,
    peer: Option<SocketAddr>,
}

impl NetIOPlugin {
    pub fn new(listen: u16, peer: Option<SocketAddr>) -> Self {
        Self { listen, peer }
    }
}

impl Plugin for NetIOPlugin {
    fn build(&self, app: &mut App) {
        app.init_state::<NetworkState>()
            .add_systems(
                FixedPreUpdate,
                (handle_network_input, handle_peer_change)
                    .chain()
                    .run_if(in_state(NetworkState::MultiPlayer)),
            )
            .add_systems(
                FixedUpdate,
                (heartbeat, timeout, handle_new_peer).run_if(in_state(NetworkState::MultiPlayer)),
            )
            .add_systems(
                FixedPostUpdate,
                handle_network_output.run_if(in_state(NetworkState::MultiPlayer)),
            )
            .add_event::<PeerChangeEvent>()
            .add_event::<InboundPacket>()
            .add_event::<OutboundPacket>();

        match bind_socket(self.listen) {
            Ok((send, receive)) => {
                app.insert_state(NetworkState::MultiPlayer)
                    .insert_resource(NetworkSend::new(send))
                    .insert_resource(NetworkReceive::new(receive));

                let mut peer_map = PeerMap::default();
                if let Some(socket) = self.peer {
                    let entity = app.world_mut().spawn(PeerData {
                        addr: socket.into(),
                        me: Uuid::nil(),
                    });
                    peer_map.insert(Uuid::nil(), entity.id());
                }

                app.insert_resource(peer_map);
            }
            Err(err) => {
                warn!("Failed to set up networking: {err}");
            }
        };
    }
}